Environmental Site Assessments

Before filing an RSC, the owner must hire a Qualified Person to complete a Phase One Environmental Site Assessment (ESA). A Phase One ESA investigates whether it is likely that one or more substances have contaminated all or part of the property.

If the Phase One ESA shows that contaminants may have affected a property, a Phase Two ESA will be needed. A Phase Two ESA must also be conducted by a Qualified Person and will determine the location and concentration of one or more contaminants, through sampling and analysis of soil, groundwater and/or sediment. Laboratory analysis of samples will determine whether contamination exceeds provincial site condition standards.

If a Phase Two ESA is not necessary, an RSC can be filed on the Brownfield Environmental Site Registry.

Beginning July 1, 2011, the minimum requirements for Phase One and Two ESAs prepared in order to file an RSC will change. At that time, Ontario will also put in place revised soil and groundwater site condition standards that have been updated to reflect advances in science, and to strengthen protection of human health and the environment.